public class AimToTen {
	  public int need(int[] marks) {
	    double sum = 0;
	    double number = marks.length;
	    int num_moreHW = 0;
	    
	    for( int num:marks )
	      sum += num;
	    
	    if ( sum/number >= 9.5 )
	      return 0;

	    else {
	         while( sum/number < 9.5 )
	          {sum += 10;
	           number++;
	           num_moreHW++;
	          }
	         }

	  return num_moreHW;
	  }
	}
